"Turn To Stone" and "Don't Bring Me Down". Can't do any better.
After you discover ELO, you can go back further. Before ELO, Roy Wood and Jeff Lynne were part of a super 60's group called The Move, who have their own colorful history, and a long string of hits.
I highly recommend from their later days, "When Alice Comes Back to the Farm".
Has all the blueprints for what would become ELO right there.
Happy listening.